CN115211800A

CN115211800A - Endoscope imaging device and endoscope

Info

Publication number: CN115211800A
Application number: CN202210400946.1A
Authority: CN
Inventors: 内藤圭介
Original assignee: Fujifilm Corp
Current assignee: Fujifilm Corp
Priority date: 2021-04-21
Filing date: 2022-04-14
Publication date: 2022-10-21
Also published as: JP2022166538A

Abstract

The invention provides an endoscope image pickup device and an endoscope, which have high bonding strength of a signal cable and high bonding reliability of the signal cable. An endoscopic imaging device is provided with: a lens barrel having an imaging lens provided therein; an imaging element that receives light having passed through the imaging lens and performs photoelectric conversion; a circuit substrate electrically connected to the imaging element; at least one optical component disposed between the lens barrel and the imaging element; a holding member that connects the optical member and the lens barrel; a signal cable electrically connected to the imaging element and having an outer sheath constituting an outer periphery; a fixing member provided on an outer sheath of the signal cable; a protection tube covering the sheath of the signal cable; and a connecting member for holding the signal cable provided with the fixing member with respect to the holding member. The signal cable is fixed to the connecting member, and the protective tube is provided so that the distal end surface is positioned closer to the lens barrel side than the rear end surface of the connecting member on the side opposite to the lens barrel and closer to the rear end surface side than the fixing member.

Description

Endoscope imaging device and endoscope

Technical Field

The present invention relates to an endoscopic imaging apparatus and an endoscope for acquiring an image of an observation target, and more particularly to an endoscopic imaging apparatus and an endoscope in which a fixing member and a protective tube are provided on a signal cable.

Background

In recent years, diagnosis and the like using an endoscope system including a light source device for an endoscope, an endoscope (endoscope scope), and a processor device have been widely performed.

The endoscope has an insertion portion to be inserted into a body of a subject, and illumination light from the light source device for endoscope is irradiated to an observation target through the insertion portion. The endoscope captures an observation object irradiated with illumination light by an imaging element and generates an image signal. The processor device performs image processing on an image signal generated by the endoscope to generate an observation image for display on a monitor. The imaging element is electrically connected to a signal cable via a circuit board such as a flexible wiring board, and the signal cable is electrically connected to the processor device.

The signal cable is a composite multi-core cable having a plurality of signal lines. Since the signal cable is inserted through the entire length of the insertion portion, the insertion portion is strongly pulled each time it is looped or bent. Therefore, a large force may be applied to the signal cable, and in this case, the connection portion between the signal cable and the circuit board may be peeled off or the signal cable may be disconnected. In order to avoid such peeling of the signal cable from the circuit board or disconnection of the signal cable, various proposals have been made.

For example, patent document 1 describes an endoscope including: a tip end body having an observation window and a lens barrel mounting hole formed at a position facing the observation window; a lens barrel mounted in the barrel mounting hole; a solid imaging element that photoelectrically converts an optical image imaged via the lens barrel; a substrate on which a solid imaging element is mounted; a signal cable including a plurality of bare wires electrically connected to the substrate and a sheath covering the bare wires; a cable mounting member having a cable fixing portion with one end fixed to the locking portion and the other end fixed to the sheath of the signal cable; and a locking receiving part formed in the tip part main body near the lens barrel mounting hole and holding the locking part in a freely swinging manner.

Patent document 1: japanese patent laid-open No. 2012-170765

Disclosure of Invention

The endoscope of patent document 1 includes: a cable mounting member having a cable fixing portion to which a sheath of the signal cable is fixed; and a locking receiving part formed in the tip part main body near the lens barrel mounting hole and holding the locking part in a freely swinging manner. However, in the endoscope of patent document 1, when the insertion portion is strongly pulled in a loop shape or a bent shape as described above, if a large force is applied to the signal cable, the signal cable may be peeled off from the circuit board or the signal cable may be disconnected.

The invention aims to provide an endoscope image pickup device and an endoscope, which have high bonding strength of a signal cable and high bonding reliability of the signal cable.

In order to achieve the above object, an aspect of the present invention provides an endoscopic imaging apparatus that acquires an image of an observation target, the endoscopic imaging apparatus including: a lens barrel having an imaging lens provided therein; an imaging element that receives light having passed through the imaging lens and performs photoelectric conversion; a circuit substrate electrically connected to the imaging element; at least one optical component disposed between the lens barrel and the imaging element; a holding member that connects the optical member and the lens barrel; a signal cable electrically connected to the imaging element and having an outer sheath constituting an outer periphery; a fixing member provided on an outer sheath of the signal cable; a protection tube covering the sheath of the signal cable; and a connecting member for holding the signal cable provided with the fixing member with respect to the holding member, wherein the signal cable is fixed to the connecting member, and the protective tube is provided such that a front end surface thereof is positioned closer to the lens barrel side than a rear end surface of the connecting member on the side opposite to the lens barrel and closer to the rear end surface side than the fixing member.

Preferably, the signal cable is fixed to the connecting member by an adhesive.

Preferably, the protective tube is softer than the adhesive in a cured state.

Preferably, the connecting member covers the imaging element, the circuit board, and the optical member.

Preferably, the connecting member is provided with a through hole.

The opening diameter of the through hole provided in the connecting member is preferably 0.6mm or more.

Preferably, the through hole provided in the connecting member is provided closer to the fixing member than the distal end surface of the protective tube.

Preferably, the imaging element, the circuit board, and the optical member are covered with a cover provided on the connecting member, and the cover is made of metal.

Preferably, a clearance is provided between the inner surface of the protective tube and the outer sheath of the signal cable.

Preferably, the protective pipe is disposed with a gap provided between an end of the connecting member of the fixing member on the rear end face side and a distal end face of the protective pipe.

An aspect of the present invention provides an endoscope including the endoscopic imaging device according to the present invention.

Effects of the invention

According to the present invention, it is possible to provide an endoscope imaging apparatus and an endoscope having high bonding strength of a signal cable and high bonding reliability of the signal cable.

Drawings

Fig. 1 is a schematic diagram showing an example of an endoscope system according to an embodiment of the present invention.

Fig. 2 is a schematic perspective view showing example 1 of an endoscopic imaging apparatus according to an embodiment of the present invention.

Fig. 3 is a schematic front view showing a 1 st example of an endoscopic imaging apparatus according to an embodiment of the present invention.

Fig. 4 is a schematic side view showing example 1 of an endoscopic imaging apparatus according to an embodiment of the present invention.

Fig. 5 is a schematic bottom view showing example 1 of the endoscopic imaging apparatus according to the embodiment of the present invention.

Fig. 6 is a schematic perspective view showing example 2 of an endoscopic imaging apparatus according to an embodiment of the present invention.

Fig. 7 is a schematic side view showing example 2 of an endoscopic imaging apparatus according to an embodiment of the present invention.

Fig. 8 is a schematic cross-sectional view showing an example of a signal cable of the endoscopic imaging apparatus according to the embodiment of the present invention.

Fig. 9 is a schematic perspective view showing example 3 of an endoscopic imaging apparatus according to an embodiment of the present invention.

Fig. 10 is a schematic perspective view showing a coupling member of example 3 of an endoscopic imaging apparatus according to an embodiment of the present invention.

Fig. 11 is a schematic side view showing example 3 of an endoscopic imaging apparatus according to an embodiment of the present invention.

Fig. 12 is a schematic perspective view showing example 4 of an endoscopic imaging apparatus according to an embodiment of the present invention.

Description of the symbols

10-endoscope system, 12-endoscope, 14-light source device, 16-processor device, 20a, 20b, 20C-endoscope image pickup device, 22-lens barrel, 23-imaging lens, 24-holding member, 24 a-mounting cylinder portion, 24 b-flange portion, 24C-convex portion, 24 e-back surface, 25-imaging element, 25 a-light receiving surface, 26, 46-circuit board, 26 a-plate portion, 26b, 46C-1 st curved portion, 26C, 46D-2 nd curved portion, 27-prism, 27 a-incident surface, 27 b-exit surface, 27C-side surface, 28-signal cable, 28 a-signal line, 28 b-cladding layer, 28C-shielding conductor, 28D-outer skin, 29-connecting member, 29 a-arm portion, 29 b-holding portion, 29C, 44 h-back end surface, 30 a-electronic member, 31-cover glass, 32-sensor protecting portion, 33-filling member, 34-36-fixing member, 37-37 a-holding portion, 44 b-inner end surface, 44 g-opening portion, 44 e-base end surface, 44 b-holding portion, 45-inner end surface, 44 b-base end surface, 44 b-side surface, 28C-side surface, 28-opening portion, 28 a-opening portion, 44 b-opening portion, 40-side surface, 44-base portion, 44 b-side portion, and inner side surface portion.

Detailed Description

Hereinafter, an endoscopic imaging apparatus and an endoscope according to the present invention will be described in detail with reference to preferred embodiments shown in the drawings.

The drawings described below are exemplary drawings for describing the present invention, and the present invention is not limited to the drawings described below.

The terms "parallel", "perpendicular" and "orthogonal" as used herein include the error ranges that are generally accepted in the art.

[ endoscope System ]

The endoscope system irradiates illumination light (not shown) to an observation site such as the inside of a subject as an observation target, images the observation site, generates a display image of the observation site from an image signal obtained by the imaging, and displays the display image.

The endoscope system 10 includes an endoscope 12, a light source device 14, and a processor device 16. The endoscope system 10 has the same configuration as a normal endoscope except for a portion of an endoscopic imaging device 20 (see fig. 2) of an endoscope 12 described later.

The endoscope 12 has an endoscope image pickup device. Although not shown in detail, the endoscope 12 includes an insertion portion to be inserted into the subject, an operation portion connected to the insertion portion, and a universal cord extending from the operation portion, and the insertion portion includes a distal end portion, a bending portion connected to the distal end portion, and a flexible portion connecting the bending portion and the operation portion. The endoscope imaging device will be described later.

An endoscope imaging apparatus 20 (see fig. 2) having an illumination optical system that emits illumination light for illuminating an observation site, an imaging device that images the observation site, an imaging optical system, and the like is provided at a distal end portion of the endoscope 12. The bending portion is configured to be bendable in a direction orthogonal to the longitudinal axis of the insertion portion, and the bending operation of the bending portion is operated by the operation portion. The flexible portion is configured to be relatively flexible to the extent that it can be deformed in conformity with the shape of the insertion path of the insertion portion.

The operation section is provided with a button for operating the image capturing operation of the endoscopic image capturing apparatus 20 (see fig. 2) at the distal end section, a knob for operating the bending operation of the bending section, and the like. An introduction port through which a treatment instrument such as an electric scalpel is introduced is provided in the operation portion, and a treatment instrument channel through which a treatment instrument such as a forceps is inserted is provided inside the insertion portion and extends from the introduction port to the distal end portion.

A connector is provided at the distal end of the universal cord, and the endoscope 12 is connected via the connector to a light source device 14 that generates illumination light emitted from an illumination optical system of the distal end portion and a processor device 16 that processes a video signal acquired by an endoscopic imaging device 20 (see fig. 2) of the distal end portion.

The processor device 16 processes the input video signal to generate video data of the observation site, and displays the generated video data on a monitor (not shown) or records the video data on a storage medium such as a hard disk. The processor device 16 may be a processor such as a personal computer.

The light source device 14 is a device for capturing an image of an observation target site in a body cavity by an endoscopic image pickup device 20 (see fig. 2) of the endoscope 12, acquiring an image signal of the observation target, generating illumination light such as white light composed of 3 primary color light such as red light (R), green light (G), and blue light (B) or specific wavelength light, supplying the illumination light to the endoscope 12, propagating through a light guide or the like in the endoscope 12, emitting the illumination light from an illumination optical system at a distal end portion of an insertion portion of the endoscope 12, and illuminating the observation target site in the body cavity.

An optical waveguide or a group of electric wires (signal cables) are housed inside the insertion portion, the operation portion, and the universal cord. The illumination light generated by the light source device 14 is guided to the illumination optical system of the tip portion via the light guide, and at least one of a signal and power is transmitted between the endoscopic imaging device 20 (refer to fig. 2) of the tip portion and the processor device 16 via the wire group.

The endoscope system 10 may further include a water supply tank for storing washing water or the like, a suction pump for sucking a suction material in the body cavity (including the supplied washing water or the like), and the like. The endoscope may further include a supply pump or the like for supplying cleaning water in the water supply tank or a gas such as external air to a pipe line (not shown) in the endoscope.

[ case 1 of endoscopic imaging device ]

Fig. 2 is a schematic perspective view showing a 1 st example of an endoscopic imaging apparatus according to an embodiment of the present invention, fig. 3 is a schematic front view showing the 1 st example of the endoscopic imaging apparatus according to the embodiment of the present invention, fig. 4 is a schematic side view showing the 1 st example of the endoscopic imaging apparatus according to the embodiment of the present invention, and fig. 5 is a schematic bottom view showing the 1 st example of the endoscopic imaging apparatus according to the embodiment of the present invention. Fig. 4 shows a state where the coupling member 29 of fig. 2 is removed.

An endoscopic imaging device 20 shown in fig. 2 is mounted on a distal end portion of an endoscope 12 of an endoscope system 10 shown in fig. 1. The endoscopic imaging device 20 is also referred to as a camera.

The endoscopic imaging apparatus 20 shown in fig. 2 and 3 acquires an image of an observation target. The endoscopic imaging apparatus 20 includes an imaging lens 23, a lens barrel 22 holding the imaging lens 23, a holding member 24, an imaging element 25, a circuit board 26, a prism 27, and a signal cable 28. The endoscopic imaging device 20 further includes a coupling member 29.

The prism 27 is, for example, a rectangular prism having an incident surface 27a orthogonal to an emission surface 27 b. The prism 27 is an example of an optical member disposed between the lens barrel 22 and the imaging element 25, and the optical member is not limited to the prism 27. The prism 27 is not necessarily required depending on the position of the imaging element 25, and may be configured to dispose other optical components.

The imaging lens 23 is an optical element that images light incident on the imaging lens 23 on a light receiving surface 25a of the imaging element 25. The imaging lens 23 is held by the lens barrel 22.

The lens barrel 22 is a cylindrical member, and holds one or more imaging lenses 23 therein. The lens barrel 22 holds the imaging lens 23 such that the optical axis C of the imaging lens 23 is perpendicular to the incident surface 27a of the prism 27. The endoscopic imaging apparatus 20 has, for example, 3 imaging lenses 23 and is held by a lens barrel 22.

Here, a direction parallel to the optical axis C is referred to as an X direction. Of the two directions orthogonal to the optical axis C, one direction is set as the Y direction, and the remaining direction is set as the Z direction. The Y direction corresponds to the width direction of the endoscopic imaging device 20, and the Z direction corresponds to the height direction of the endoscopic imaging device 20.

The structures of the imaging lens 23 and the lens barrel 22 are not particularly limited. For example, the configuration may be one imaging lens 23, or may be 2 or 4 or more imaging lenses 23. Each imaging lens 23 may be a convex lens or a concave lens.

The imaging element 25 is an imaging element that performs photographing by converting light imaged by the imaging lens 23 into an electric signal by photoelectric conversion. The imaging element 25 is a conventionally known imaging element, and a CCD (charge Coupled Device) type image sensor or a CMOS (Complementary Metal Oxide Semiconductor) image sensor can be used.

The imaging element 25 is disposed on the base end side of the lens barrel 22. As shown in fig. 3 and 4, the imaging element 25 is electrically connected to the circuit board 26 via a bump 34 having conductivity, for example. As shown in fig. 4, the imaging element 25 is mounted on the circuit board 26 such that the light receiving surface 25a is parallel to the optical axis C of the imaging lens 23. In addition, mounting refers to electrical connection.

An underfill layer (not shown) may be provided between the imaging element 25 and the circuit board 26 in order to firmly connect the imaging element 25 and the circuit board 26.

The bump 34 is composed of a metal or an alloy. More specifically, the bump 34 is made of solder. The bumps 34 formed of solder are also referred to as solder balls. The bumps 34 are not limited to solder or the like as long as the imaging element 25 and the circuit board 26 can be electrically connected to each other. The imaging element 25 and the circuit board 26 may be directly electrically connected.

Further, due to the difference in the thermal expansion coefficient between the imaging element 25 and the circuit board 46, stress is generated in the joint portion between the imaging element 25 and the circuit board 26, for example, in the bump 34, but the underfill layer relaxes the stress. The imaging element 25 and the circuit board 26 are firmly connected by the underfill layer, and the reliability of electrical connection is increased, thereby obtaining the highly reliable endoscopic imaging device 20.

The underfill agent constituting the underfill layer is not particularly limited, and an underfill agent serving as a sealing resin between the imaging element 25 and the circuit board 26 can be suitably used. For example, a one-component heat-curable epoxy resin is used as the underfill. In this case, after the underfill agent is supplied, the underfill layer is formed by heating and maintaining the temperature at a predetermined temperature.

The circuit substrate 26 is a substrate on which the imaging element 25 is mounted. Further, for example,

electronic components

30 and 30a are mounted on the circuit board 26 in addition to the imaging element 25.

The circuit board 26 is provided with a plurality of connection terminals (not shown) for inputting and outputting signals and power to and from the imaging element 25 and the

electronic components

30 and 30a. The signal line 28a (refer to fig. 4) of the signal cable 28 is electrically connected to the connection terminal.

In the illustrated example, the circuit board 26 has a shape in which a substantially L-shaped plate-like member is bent at 2. Specifically, the circuit board 26 has a 1 st bent portion 26b bent around the direction orthogonal to the optical axis C direction of the imaging lens 23 and a 2 nd bent portion 26C bent around the optical axis C direction, and the imaging element 25, the

electronic components

30 and 30a, and the connection terminals are mounted on 3 plate-like portions connected by the two bent portions. The imaging element 25 is mounted on the upper surface side of the plate-like portion 26a of the lower circuit board 26 in fig. 4.

The circuit board 26 may be a flexible board. The circuit board 26 may be bent at 1 or 3 or more. The arrangement of the imaging element 25, the

electronic components

30 and 30a, the connection terminals, and the like on the circuit board 26 is not particularly limited. The circuit board 26 is formed of, for example, a flexible printed circuit board.

The signal cable 28 is connected to a connection terminal on the circuit board 26, and the imaging element 25 is electrically connected to the signal cable 28. The light is converted into an electrical signal by the imaging element 25, and the electrical signal is transmitted via the signal cable 28. The signal cable 28 is inserted into an insertion portion, an operation portion, a universal cord, and the like of the endoscope, and is electrically connected to the processor device 16 (see fig. 1). The signal cable 28 is not particularly limited as long as it has a sheath 28d constituting the outer periphery.

For example, as shown in fig. 4, the signal cable 28 has: a plurality of signal lines 28a; a coating layer 28b for coating each signal line 28a; a shield conductor 28c provided around the entire plurality of signal lines 28a and covered with the covering layer 28b; and a sheath 28d covering the shield conductor 28c. As described above, the sheath 28d constitutes the outer periphery of the signal cable 28. The coating layer 28b, the shield conductor 28c, and the sheath 28d are cylindrical, for example. The shield conductor 28c of the signal cable 28 is referred to as a shield. The signal cable 28 has, for example, 4 signal lines 28a. The number of signal lines 28a is not particularly limited according to the configuration of the endoscopic imaging device 20, and may be 2, 3, or 5 or more.

The signal cable 28 is a multi-core cable in which a plurality of signal wires 28a are bundled, a shield conductor 28c is provided around the signal cable, and the signal cable is housed in a cylindrical sheath 28d.

The cover glass 31 is disposed on the light receiving surface 25a of the imaging element 25 and protects the light receiving surface 25a.

The prism 27 is disposed between the lens barrel 22 and the imaging element 25 via a cover glass 31. The prism 27 guides the light that has passed through the imaging lens 23 to the light receiving surface 25a of the imaging element 25. The prism 27 bends the light passing through the imaging lens 23 held by the lens barrel 22 by, for example, 90 ° to change the optical path, and guides the light to the light receiving surface 25a of the imaging element 25. The prism 27 is disposed so that the incident surface 27a faces the proximal end side of the lens barrel 22. The prism 27 is disposed such that the emission surface 27b faces the light receiving surface 25a of the imaging element 25. In this case, the prism 27 is disposed on the cover glass 31 such that the emission surface 27b faces the cover glass 31.

The holding member 24 is a member that holds the lens barrel 22 and the prism 27. The holding member 24 is a substantially cylindrical member, and the lens barrel 22 is fitted into the cylindrical portion to hold the lens barrel 22. The inner surface of the holding member 24 is bonded and fixed to the outer peripheral surface of the lens barrel 22.

As the adhesive for adhering the holding member 24 and the lens barrel 22, various known adhesives used in conventional endoscopes can be used. This also applies to adhesives that bond other members to each other.

The holding member 24 has a polygonal flange portion 24b on the end surface on the base end side of the mounting cylindrical portion 24a, and abuts against the incident surface 27a of the prism 27. Thereby, the prism 27 is positioned. The holding member 24 holds the lens barrel 22 and the prism 27 at predetermined positions, thereby fixing the relative position between the lens barrel 22 and the prism 27, that is, the relative position between the lens barrel 22 and the light receiving surface 25a of the imaging element 25. The exit surface 27b of the prism 27 is opposed to the imaging element 25.

Here, the lens barrel 22 is fixed to the holding member 24 by being bonded thereto by adjusting the relative position thereof with respect to the holding member 24 in the direction of the optical axis C of the imaging lens 23 so as to be in focus on the light receiving surface 25a of the imaging element 25.

The coupling member 29 is a member that holds the signal cable 28 provided with the fixing member 36 (see fig. 4 and 5) with respect to the holding member 24. As shown in fig. 2, the coupling member 29 is a member formed by bending one plate member. Specifically, the connecting member 29 has a shape in which one plate material is bent at 2 bending portions extending in the optical axis C direction. Therefore, the cross section of the coupling member 29 perpendicular to the optical axis C direction is substantially C-shaped. The connecting member 29 is disposed so as to include a connection terminal (a connection point with the signal cable 28) on the circuit board 26 inside the substantially C-shape. That is, as shown in fig. 2, the coupling member 29 is disposed so as to cover the circuit board 26 from the upper side in the figure. The connecting member 29 also covers the imaging element 25, the prism 27, and the

electronic components

30 and 30a, and also serves as a cover member for the imaging element 25, the prism 27, and the

electronic components

30 and 30a. The coupling member 29 also functions as a protective member for the imaging element 25, the prism 27, and the

electronic components

30 and 30a.

The coupling member 29 has a pair of arm portions 29a on the distal end side. The pair of arm portions 29a engage with the flange portion 24b of the holding member 24.

The coupling member 29 has a holding portion 29b that holds the signal cable 28 on the proximal end side. The holding portion 29b is bent along the outer cover 28d, and the width from the arm portion 29a toward the rear end surface 29c and the y direction becomes narrower. The signal cable 28 is fixed and held to the holding portion 29b.

As shown in fig. 4 and 5, the signal cable 28 includes a fixing member 36 provided on the sheath 28d of the signal cable 28 and a protective tube 37 covering the sheath 28d of the signal cable 28. As described above, the signal cable 28 is fixed to the coupling member 29.

The fixing member 36 is provided on the sheath 28d of the signal cable 28, and fixes the sheath 28d to the signal line 28a of the signal cable 28 by fastening. The fixing member 36 is, for example, an annular member, and the sheath 28d is fixed to the signal line 28a of the signal cable 28 by fastening the fixing member 36 by caulking.

The fixing member 36 is not limited to a ring shape, and may be a polygonal ring-shaped member as long as the sheath 28d can be fixed to the signal line 28a of the signal cable 28. The fixing member 36 may not be annular but may be discontinuous in one circle with a gap, for example, C-ring. In this case, the separated end portions are brought close to each other by caulking so that the separated end portions are brought close to each other, the opening of the fixing member 36 is reduced, and the sheath 28d is fixed to the signal line 28a of the signal cable 28. The fixing member 36 is made of, for example, metal or alloy.

As shown in fig. 5, the protective tube 37 is provided such that the distal end surface 37a is positioned closer to the lens barrel 22 than the rear end surface 29c of the coupling member 29 on the opposite side to the lens barrel 22 and closer to the rear end surface 29c than the fixing member 36. That is, the protective tube 37 is provided on the signal cable 28 so as to overlap the coupling member 29. The distal end surface 37a of the protection tube 37 is an end surface of the protection tube 37 on the lens barrel 22 side.

When the protective tube 37 is disposed to overlap the signal cable 28 as described above, the area of the sheath 28d in the connecting member 29 is reduced. Therefore, when the signal cable 28 is fixed to the connecting member 29 using an adhesive, the adhesive area is reduced. However, by providing the fixing member 36, the fixing strength can be supplemented. Further, the strength of the connecting member 29 near the rear end surface 29c can be increased by the protective tube 37. Thus, in the signal cable 28, when the concentration of the load due to the rapid change in rigidity in the vicinity of the rear end surface 29c of the coupling member 29 is excessively large, the signal wire 28a (core wire) inside can be prevented from being damaged even if the sheath 28d of the signal cable 28 is not displaced.

As described above, the signal cable 28 used in the endoscope imaging apparatus 20 is configured to bind the plurality of signal lines 28a with the sheath 28d, and the signal lines 28a are easily damaged, and therefore need to be protected by the sheath 28d or the connecting member 29. The connecting member 29 is formed of metal or the like, and the rigidity of the rear end surface 29c of the connecting member 29 changes rapidly, so that the load on the signal cable 28 is concentrated largely. Therefore, when the sheath 28d is displaced by bending operation of the endoscope or sliding with other contents and the signal line 28a is exposed to the outside of the coupling member 29, the signal line 28a is damaged in the vicinity of the rear end surface 29c of the coupling member 29.

However, by fixing the sheath 28d of the signal cable 28 by the fixing member 36, the fixing strength of the sheath 28d of the signal cable 28 is increased, and then the protective tube 37 is fixed by being overlapped on the connecting member 29 as described above, whereby the amount of decrease in the bonding area of the sheath 28d of the signal cable 28 is compensated for by the fixing strength of the fixing member 36, and the strength in the vicinity of the rear end surface 29c of the connecting member 29 is increased by the protective tube 37. This makes it possible to obtain the endoscopic imaging apparatus 20 having high bonding strength of the signal cable 28 and high bonding reliability of the signal cable 28.

Further, since the connecting member 29 is connected to the holding member 24 and the signal cable 28, respectively, it is possible to prevent the connection between the connection terminal on the circuit board 26 and the signal line 28a of the signal cable 28 from being broken due to the connection between the connection terminal and the signal line 28a being pulled when the signal cable 28 is pulled.

The arm portion 29a of the coupling member 29 and the flange portion 24b of the holding member 24, and the holding portion 29b of the coupling member 29 and the sheath 28d of the signal cable 28 are fixed by adhesion using, for example, an adhesive 38. In the case of adhesive fixation, the adhesive 38 is in a cured state. The holding portion 29b of the coupling member 29 and the sheath 28d of the signal cable 28 may be fixed to each other, and the fixing is not limited to the adhesion using the adhesive 38.

When the protective tube 37 is fixed by bonding with the adhesive 38, it is preferable that the protective tube 37 is softer than the adhesive 38 in a cured state. Since the protective tube 37 is softer than the cured adhesive 38, the protective tube 37 can be easily bent, and the load applied to the signal cable 28 on the rear end surface 29c of the connecting member 29 is reduced. The adhesive 38 is, for example, an epoxy resin adhesive, and the protection tube 37 is, for example, PTFE (polytetrafluoroethylene). As the adhesive 38, in addition to an epoxy adhesive, for example, a silicone adhesive or an acrylic adhesive can be used.

The protective tube 37 is preferably disposed with a gap 39 provided between the end 36b of the fixed member 36 on the rear end surface 29c side of the connecting member 29 and the front end surface 37a of the protective tube 37. By providing the gap 39 and providing the fixing member 36 and the protective tube 37, the bonding area of the adhesive 38 can be secured. The signal cable 28 can be more reliably fixed to the coupling member 29. When the signal cable 28 is pulled to the opposite side of the lens barrel 22, the fixing member 36 is caught by the adhesive 38, and damage to the signal cable 28 can be suppressed.

The gap 39 is preferably 1mm or more because it can secure the bonding area of the adhesive 38. The upper limit of the gap 39 is not particularly limited because the bonding strength increases as the bonding range increases. However, due to structural limitations of the endoscopic imaging device 20, the upper limit of the gap 39 is about 3 mm. The gap 39 is measured using a micrometer or vernier caliper.

The fixing member 36 and the protective tube 37 are assembled using a jig or a device capable of positioning and assembling the respective components at predetermined positions, for example.

In the endoscope imaging apparatus 20, an observation image read from the imaging lens 23 to the imaging element 25 is imaged on the light receiving surface 25a of the imaging element 25, converted into an electric signal, output to the processor apparatus 16 (see fig. 1) via the signal cable 28, converted into a video signal, and an observation image is displayed on a monitor connected to the processor apparatus 16.

In the endoscope imaging apparatus 20, the coupling member 29 is formed of a metal material and has a sensor protection portion 32 covering the side surface of the imaging element 25. As shown in fig. 2 and 3, the coupling member 29 includes a sensor protection portion 32 extending downward in the drawing from two opposing side surfaces having a substantially C-shaped cross section.

The sensor protection portion 32 is disposed at a position where two side surfaces of the imaging element 25 parallel to the optical axis C of the imaging lens 23 overlap when viewed from a direction perpendicular to the side surfaces. The width of the sensor protection portion 32 in the direction of the optical axis C is larger than the width of the side surface of the imaging element 25, and covers the entire side surface of the imaging element 25.

In the example shown in fig. 2 and 3, the filling member 33 is preferably filled between the sensor protection portion 32 and the side surface of the imaging element 25. Therefore, the imaging element 25 is in physical contact with the joining member 29 via the filling member 33. The coupling member 29 physically contacts the holding member 24 and the signal cable 28. By covering the side surface of the imaging element 25 with the sensor protection portion 32 and filling the space between the side surface of the imaging element 25 and the sensor protection portion 32 with the filling member 33, a heat radiation path such as the filling member 33, the coupling member 29, the holding member 24, and the signal cable 28 is formed from the imaging element 25. Therefore, heat generated from the imaging element 25 can be efficiently dissipated. Also, by covering the imaging element 25 with a hard metal material, the imaging element 25 can be protected.

The metal material forming the connecting member 29 is not particularly limited, and a metal material having high thermal conductivity is preferable. In consideration of workability, acquisition properties, strength, and the like, the connecting member 29 is preferably stainless steel or a copper alloy.

As a material of the filling member 33, an adhesive or a sealant can be used. As the adhesive, various adhesives used in endoscopes can be used.

As the sealant, various sealants used in endoscopes can be used. The higher the thermal conductivity of the adhesive and the sealant, the better, but the insulating property is preferable.

The filling member 33 preferably fills the entire region between the side surface of the imaging element 25 and the sensor protection portion 32, but may fill at least a part between the side surface of the imaging element 25 and the sensor protection portion 32.

In the example shown in fig. 3, the filling member 33 is filled in the entire region between the side surface of the cover glass 31 and the sensor protection portion 32. By filling the filling member 33 also in the region between the side surface of the cover glass 31 and the sensor protection portion 32, heat from the imaging element 25 can be more efficiently transmitted.

In the example shown in fig. 2, the sensor protection portion 32 has a width larger than the width of the side surface of the imaging element 25 and covers the entire side surface of the imaging element 25, but is not limited thereto. The sensor protection portion 32 may cover at least a part of the side surface of the imaging element 25. The sensor protection portion 32 preferably covers the entire side surface of the imaging element 25 from the viewpoint of heat dissipation.

Here, in the example shown in fig. 3, the filling member 33 is provided between the side surface of the imaging element 25 and the sensor protection portion 32, but the present invention is not limited thereto, and the side surface of the imaging element 25 and the sensor protection portion 32 may be in direct contact with each other.

[ 2 nd example of endoscopic imaging device ]

The endoscopic imaging device 20 is not limited to the configuration shown in fig. 2 to 5. Hereinafter, example 2 of the endoscope image pickup apparatus will be described.

Fig. 6 is a schematic perspective view showing a 2 nd example of an endoscopic imaging device according to an embodiment of the present invention, and fig. 7 is a schematic side view showing the 2 nd example of the endoscopic imaging device according to the embodiment of the present invention. In fig. 6 and 7, the same components as those of the endoscopic imaging apparatus 20 shown in fig. 2 to 5 are denoted by the same reference numerals, and detailed description thereof is omitted.

The endoscopic imaging apparatus 20a shown in fig. 6 and 7 is different from the endoscopic imaging apparatus 20 shown in fig. 2 to 5 in that a through hole 40 is provided in the coupling member 29, and is similar to the endoscopic imaging apparatus 20 shown in fig. 2 to 5 except for the configuration. The endoscopic imaging apparatus 20a has the same effects as the endoscopic imaging apparatus 20 shown in fig. 2, such as high bonding strength of the signal cable 28 and high bonding reliability of the signal cable 28.

In the endoscope imaging device 20a, the through-hole 40 is provided, whereby the filling path of the adhesive 38 can be increased, the supply amount of the adhesive 38 can be increased, and the adhesion strength can be further improved. Further, by providing the through-hole 40, the filled state after the adhesive 38 is injected can be easily confirmed.

The opening diameter D of the through-hole 40 is preferably 0.6mm or more. If the opening diameter D is 0.6mm or more, the adhesive 38 can be easily injected using a syringe, for example.

In order to maintain the strength of the connecting member 29, the opening diameter D of the through-hole 40 is preferably 1/2 or less of the length of the connecting member 29 in the Y direction.

The opening diameter D of the through-hole 40 is measured using a micrometer, a vernier caliper, or a needle gauge.

As shown in fig. 7, the through-hole 40 provided in the connecting member 29 is preferably provided closer to the fixing member 36 than the distal end surface 37a of the protective tube 37 in the optical axis C direction. By providing the through-hole 40 at such a position, the adhesive 38 can be easily supplied to the sheath 28d of the signal cable 28, and the strength of adhesion and fixation between the signal cable 28 and the coupling member 29 can be further improved. In this case, if the through-hole 40 is provided above the gap 39, the adhesive 38 can be more reliably supplied to the sheath 28d of the signal cable 28, and therefore, the sheath 28d is more reliably adhered to the connecting member 29 by the adhesive 38, which is more preferable. The through-hole 40 may be provided above the fixing member 36.

Here, fig. 8 is a schematic cross-sectional view showing an example of a signal cable of the endoscopic imaging apparatus according to the embodiment of the present invention.

Although the sheath 28d of the signal cable 28 is covered with the protective tube 37, as shown in fig. 8, a clearance 41 is preferably provided between the inner surface 37b of the protective tube 37 and the sheath 28d of the signal cable 28. By providing the play 41 between the protective tube 37 and the signal cable 28, when the signal cable 28 is bent, the signal cable 28 is preferentially bent by the amount of the play 41 than the protective tube 37, and the protective tube 37 is bent after the signal cable 28 is bent. This reduces the load on the signal cable 28 in the vicinity of the rear end surface 29c of the coupling member 29, and suppresses damage to the signal wire 28a (core wire) of the signal cable 28.

In addition, if the clearance 41 is 0.05 to 0.2mm, the load of the signal cable 28 is reduced, and the damage of the signal line 28a (core line) of the signal cable 28 can be further suppressed. The play 41 is obtained by measuring the outer diameter of the sheath 28d of the signal cable 28 and the inner diameter of the protective tube 37 and determining the difference between the outer diameter of the sheath 28d of the signal cable 28 and the inner diameter of the protective tube 37. The outer diameter of the sheath 28d of the signal cable 28 and the inner diameter of the protective tube 37 are measured using a micrometer or a vernier caliper.

[ 3 rd example of endoscopic imaging apparatus ]

Fig. 9 is a schematic perspective view showing a 3 rd example of an endoscopic imaging apparatus according to an embodiment of the present invention, fig. 10 is a schematic perspective view showing a coupling member of the 3 rd example of the endoscopic imaging apparatus according to the embodiment of the present invention, and fig. 11 is a schematic side view showing the 3 rd example of the endoscopic imaging apparatus according to the embodiment of the present invention. Fig. 11 shows a state where the coupling member 44 of fig. 9 is removed. In fig. 9 to 11, the same components as those of the endoscopic imaging apparatus 20 shown in fig. 2 to 5 are denoted by the same reference numerals, and detailed description thereof is omitted.

The endoscopic imaging apparatus 20b is basically the same as the endoscopic imaging apparatus 20 shown in fig. 2 to 5 except that the coupling member 44 and the circuit board 46 have different structures from the endoscopic imaging apparatus 20 (see fig. 2).

As shown in fig. 9, the endoscopic imaging apparatus 20b includes: a lens barrel 22; a holding member 24; an imaging element 25; a circuit substrate 46 on which the imaging element 25 and the

electronic components

30 and 30a are arranged; and a connecting member 44 for holding the signal cable 28 with respect to the holding member 24. As shown in fig. 11, the imaging element 25 is electrically connected to the circuit substrate 46 via the bump 34 having conductivity. An underfill layer (not shown) provided between the imaging element 25 and the circuit board 46 may be provided. The

electronic components

30 and 30a are electrically connected to the circuit board 46.

The endoscopic imaging device 20b further includes an engagement portion 42 for engaging the holding member 24 with the coupling member 44.

Here, as shown in fig. 9 and 11, a direction parallel to the optical axis C is referred to as an X direction. Of the two directions orthogonal to the optical axis C, one direction is set as the Y direction, and the remaining direction is set as the Z direction. The Y direction corresponds to the width direction of the endoscopic imaging device 20b, and the Z direction corresponds to the height direction of the endoscopic imaging device 20b.

The holding member 24 has a cylindrical mounting cylindrical portion 24a fitted to the outer periphery of the lens barrel 22 and a flange portion 24b integrally connected to the mounting cylindrical portion 24 a. A prism 27 is provided on the back surface 24e of the flange portion 24b.

The prism 27 is, for example, a rectangular prism having an incident surface 27a and an exit surface 27b orthogonal to each other. The incident surface 27a is disposed toward the back surface 24e of the flange 24b. Thereby, the incident surface 27a faces the imaging lens 23.

A cover glass 31 is disposed on the imaging element 25. A prism 27 is disposed on the cover glass 31, and an emission surface 27b of the prism 27 faces the imaging element 25.

The imaging element 25 is provided on a surface 46a of one end of the circuit board 46, for example, in parallel with the optical axis C of the imaging lens 23, and is disposed below the flange portion 24b of the holding member 24. A plurality of connection terminals (not shown) for inputting and outputting signals or power to and from the imaging element 25 and the

electronic components

30 and 30a are provided on the back surface 46b of the circuit board 46 on the side opposite to the light-receiving surface 25a of the imaging element 25.

The circuit board 46 is made of, for example, a flexible substrate. The flexible substrate is, for example, a flexible wiring substrate. For example, as shown in fig. 11, the circuit board 46 is bent at two positions, and has a 1 st bent portion 46c and a 2 nd bent portion 46d. Between the 1 st bent portion 46c and the 2 nd bent portion 46d, for example, two electronic components 30 are provided on the surface 46a of the circuit board 46. On the surface 46a of the circuit board 46 connected to the 2 nd bent portion 46d, for example, 3 electronic components 30 and two electronic components 30a are provided.

By bending the circuit board 46 at two positions to provide the 1 st bending portion 46c and the 2 nd bending portion 46d, the size can be reduced in the X direction, and the endoscopic imaging device 20b can be downsized in the X direction. In other words, the endoscopic imaging device 20b can be shortened. As shown in fig. 11, the signal line 28a of the signal cable 28 is electrically connected to a connection terminal (not shown) provided on the rear surface 46b of the other end of the circuit board 46.

The bending of the circuit board 46 is not limited to two positions, and may be determined appropriately according to the device configuration such as the number of

electronic components

30 and 30a, the size of the device, and the like. As described above, the imaging element 25 is electrically connected to the circuit board 46 via the conductive bump 34, and as described above, an underfill layer may be provided between the imaging element 25 and the circuit board 46. The underfill layer is as described above.

The bumps 34 having conductivity are connected to electrodes provided on the connection surface of the imaging element 25 to the circuit substrate 46. The bump 34 is electrically connected to the wiring layer of the circuit board 46.

In the endoscope imaging apparatus 20b, at least one optical member is arranged between the lens barrel 22 and the imaging device 25. The optical member is not particularly limited to the prism 27.

The engaging portion 42 has at least one convex portion provided on the holding member 24 and a concave portion provided on the coupling member 44 and engaged with the convex portion of the holding member 24. In the engaging portion 42, the convex portion of the holding member 24 is engaged with the concave portion of the coupling member 44, whereby the holding member 24 and the coupling member 44 can be firmly fixed. The recess of the coupling member 44 further includes an opening through which a member to be described later passes.

The flange portions 24b of the holding member 24 shown in fig. 9 and 11 are provided with two convex portions 24c facing each other with the prism 27 interposed therebetween. The two protrusions 24c cover a part of the side surface 27c of the prism 27, and the prism 27 is fixed by sandwiching the prism 27 between the two protrusions 24c. The two convex portions 24c have the same shape and size, and the convex portions 24c are provided on both sides of the flange portion 24b of the holding member 24. The side surface 27c of the prism 27 is a surface perpendicular to the incident surface 27a and the emission surface 27 b.

In the holding member 24, the convex portion 24c (see fig. 9 and 11) of the flange portion 24b has a quadrangular external shape, for example, but one corner is cut out. Therefore, the convex portion 24c (see fig. 9 and 11) of the flange portion 24b is substantially pentagonal.

The coupling member 44 holds the signal cable 28 with respect to the holding member 24.

For example, as shown in fig. 10, the coupling member 44 includes a holding portion 44a, and the holding portion 44a includes a flat bottom portion 44f formed by bending one plate material and a flat base portion 44g connected to the bottom portion 44 f. The connecting member 44 has a base end 45a on the side of the holding portion 44 a. The base material portion 44g is bent along the sheath 28d of the signal cable 28. The signal cable 28 is fixed to the connecting member 44 by bonding with an adhesive 38 (see fig. 11), for example.

The arm portions 44b are provided on the flat plate-like base material portions 44g of the holding portion 44a facing each other with the opening therebetween. The coupling member 44 has a pair of arm portions 44b. The arm portion 44b is bent outward more than the holding portion 44a on the base end 45a side, and then extends linearly. Therefore, the distance between the distal ends 45b of the pair of arm portions 44b is wider than the distance between the proximal ends 45a, and the distance is appropriately determined according to the convex portions 24c of the holding member 24 shown in fig. 9. Further, an opening 44c is provided at the tip 45b of each arm 44b.

The opening 44c of the arm 44b engages with the projection 24c of the holding member 24. The opening 44c is formed by, for example, cutting a part of the arm 44b into a rectangular shape.

The size and shape of the opening 44c may be the same as the external shape of the projection 24c. Here, the opening 44c is the same in size and shape as the external shape of the projection 24c, and means that the error range that is generally allowable in the technical field is included. Therefore, the opening 44c and the projection 24c may be in any one of a so-called clearance fit, a transition fit, and an interference fit.

In the following description, "the same size and shape" means that the error range which is generally allowed in the technical field is included as described above.

As described above, by having the engaging portion 42 for engaging the opening portions 44C of the pair of arm portions 44b with the convex portions 24C of the holding member 24, the concave portions are fitted to the convex portions, so that the length of the endoscopic imaging device 20b in the Y direction orthogonal to the optical axis C can be shortened, and the increase in size of the endoscopic imaging device 20b can be suppressed. Further, the holding member 24 and the coupling member 44 can be firmly fixed.

Further, by matching the thickness of the arm portions 44b with the height of the convex portions 24C, when the opening portions 44C of the pair of arm portions 44b are engaged with the convex portions 24C of the holding member 24, respectively, the length of the endoscopic imaging device 20b in the Y direction orthogonal to the optical axis C can be shortened, and with this configuration, the endoscopic imaging device 20b can be further downsized.

In the connecting member 44, the pair of arm portions 44b are preferably bent so as to be closer to each other on the distal end 45b side than on the proximal end 45a side of the arm portions 44b. That is, the pair of arm portions 44b are preferably bent in the closing direction. Thus, by widening the primary arm portion 44b, the opening portion 44c of the arm portion 44b can be fitted to the projection portion 24c of the holding member 24, and assembly can be easily performed.

As described above, the pair of arm portions 44b are preferably bent so as to be closer to each other on the distal end 45b side than on the proximal end 45a side of the arm portions 44b, but this may be a component state before assembly.

Further, the arm portion 44b is provided with the opening portion 44c that penetrates therethrough, but is not limited thereto, and may be a recess portion having a bottom portion that is recessed without penetrating therethrough.

In the coupling member 44, the signal cable 28 is fixed and held on the inner side 44e of the holding portion 44a by, for example, the adhesive 38. The method of fixing the signal cable 28 is not particularly limited as long as the signal cable 28 does not fall off from the holding portion 44a or the signal line 28a when the endoscope is used. The signal cable 28 is fixed to the coupling member 44 by bonding with an adhesive 38, for example.

As shown in fig. 11, in the endoscopic imaging apparatus 20b, the sheath 28d of the signal cable 28 is provided with a fixing member 36 and covered with a protective tube 37, similarly to the endoscopic imaging apparatus 20. Therefore, in the endoscope imaging apparatus 20b, as in the endoscope imaging apparatus 20, the bonding strength of the signal cable 28 is high, and the bonding reliability of the signal cable 28 is high.

In the endoscopic imaging apparatus 20b, as in the endoscopic imaging apparatus 20 (see fig. 4), as shown in fig. 11, a gap 39 is preferably provided between the end portion 36b of the fixing member 36 on the rear end surface 44h side of the coupling member 44 and the distal end surface 37a of the protective tube 37. As shown in fig. 8, a clearance 41 is preferably provided between the inner surface 37b of the protective tube 37 and the outer sheath 28d of the signal cable 28.

In the holding member 24, the two projections 24c may be identical in size and shape, that is, identical, as described above, but may be different in size and shape.

In the holding member 24, the shape of the convex portion is not particularly limited to the above-described quadrangle, and may be a circle, an ellipse, a triangle, a polygon such as a pentagon or a hexagon, or a combination of these shapes. Further, the shape may be not only one, but also a shape in which a plurality of convex portions having the same shape are arranged, or a specific pattern.

In the engaging portion 42, one convex portion and one concave portion are engaged at one location, but the engaging location is not limited to one, and a plurality of engaging locations may be provided at one convex portion.

The size of the convex portion of the holding member 24 is preferably, for example, a size that covers at least a part of the side surface 27c of the prism 27. By setting the size of the convex portion to a size covering at least a part of the side surface 27c of the prism 27, the prism 27 can be more stably sandwiched and fixed, and can be used for positioning the prism in the Y direction with respect to the holding member at the time of assembly.

The upper limit of the size of the convex portion of the holding member 24 can be set to a size that completely covers the side surface 27c of the prism 27.

In the holding member 24, the two convex portions 24c are provided to face each other, and the arm portion 44b surrounds the prism 27 and the circuit board 46. This stabilizes the engagement between the holding member 24 and the coupling member 44, and also protects the prism 27 and the circuit board 46.

The holding member 24 has a structure in which two convex portions 24c are provided, but the size is not limited thereto, and 3 or more convex portions may be provided as long as the size is not increased. That is, the number of the engaging portions may be 3 or more.

The prism 27 is a member for guiding the light of the imaging lens 23 to the imaging element 25, and is not limited to a right-angled prism, and a shape corresponding to the arrangement position of the imaging element 25 may be appropriately used as the shape of the prism 27. The prism 27 is not necessarily required depending on the position of the imaging element 25, and may be configured to dispose other optical components.

For example, by using the prism 27 that bends the optical axis C of the imaging lens 23 at a right angle, the degree of freedom in the arrangement position of the imaging element 25 can be increased, and a large imaging element 25 can be used without being limited by the size of the flange portion 24b of the holding member 24 or the like.

After the holding member 24 and the prism 27 are fixed to each other by adhesion, they are sandwiched between the side surface arm portions 44b, and the arm portions 44b are connected to the holding member 24 and the prism 27 by adhesion. The joining of the holding member 24 and the prism 27 is also made stronger by bonding the arm portion 44b from the side. Further, by bonding the side surface 27c of the prism 27 to the arm portion 44b in addition to the side surface of the holding member 24, the fixing strength of the arm portion 44b is also improved.

The coupling strength between the holding member 24 and the arm portion 44b is increased by the protruding portion 24c and the opening portion 44c (recessed portion) having the same shape and the same size, and by receiving forces in the X direction and the Z direction in the cross section of the arm portion.

The bent portion 46e is an end portion on the 1 st bent portion 46c side, and is a bending start point of the 1 st bent portion 46c of the circuit board 46.

The endoscopic imaging device 20b is imaged by X-rays, and a cross-sectional image of the circuit board 46 is obtained. In the cross-sectional image of the circuit board 46, the position of the bending start point of the 1 st bent portion 46c of the circuit board 46 can be specified, and the above-described bent portion 46e can be specified.

In addition, the position of the bending start point is a connection position of the 1 st bent portion 46c and the circuit substrate 46 below the imaging element 25. Therefore, the 1 st bent portion 46c is determined, and the connection position can be determined assuming that the circuit board 46 is a plane.

For example, in the circuit board 46, the imaging element 25 and the electronic component 30 are arranged at predetermined positions on the surface 46 a. The signal line 28a of the signal cable 28 is electrically connected to a connection terminal (not shown) provided on the rear surface 46 b. When the circuit board 46 is unfolded, that is, when the circuit board is in a state before being bent, the signal cable 28 extends to a side opposite to a side where the imaging element 25 is arranged. With this configuration, workability in electrically connecting the signal cable 28 and the circuit board 46 by soldering or the like is improved, and assembly workability is also improved.

The circuit board 46 has the same structure as the circuit board 26, and is formed of a flexible printed circuit board.

The circuit board 46 is bent at two points, for example, but it is preferable that all the bending directions of the circuit board 46 are bent in the same direction. Thus, as in the 1 st bending portion 46c and the 2 nd bending portion 46d, there is no bending region in the Y direction of the endoscope imaging device 20b, and the ratio of the bending region in the space inside the endoscope imaging device 20b can be reduced.

The imaging element 25 and the

electronic components

30 and 30a are provided on the surface 46a of the circuit board 46, but the present invention is not limited thereto, and the imaging element 25 and the

electronic components

30 and 30a may be provided on different surfaces.

Further, the imaging element 25 and the

electronic components

30 and 30a are preferably provided on one circuit substrate 46. By providing the circuit board 46, the number of components can be reduced.

The

electronic components

30 and 30a are used for driving the imaging element 25, and are not particularly limited, and examples thereof include a voltage regulator, a resistor, and a capacitor. The voltage regulator stabilizes the voltage applied to the imaging element 25, and outputs a constant voltage to the imaging element 25.

In the circuit board 46, for example, the rear surface 46b of the circuit board 46 and the shield conductor 28c of the signal cable 28 may be joined to each other by, for example, solder at the other end. By joining the shield conductor 28c of the signal cable 28 to the rear surface 46b, heat generated from the imaging element 25 and the electronic component 30 can be discharged from the circuit board 46 to the outside of the endoscopic imaging apparatus 20b via the signal cable 28, and the heat dissipation of the endoscopic imaging apparatus 20b can be improved.

[ 4 th example of endoscopic imaging apparatus ]

Fig. 12 is a schematic perspective view showing example 4 of an endoscopic imaging apparatus according to an embodiment of the present invention. In fig. 12, the same components as those of the endoscopic imaging apparatus 20b shown in fig. 9 and 11 and the coupling member 44 shown in fig. 10 are denoted by the same reference numerals, and detailed description thereof will be omitted.

The endoscopic imaging apparatus 20c shown in fig. 12 is different from the endoscopic imaging apparatus 20b shown in fig. 9 in that it has a cover 50, and is otherwise the same as the endoscopic imaging apparatus 20b shown in fig. 9 and 11.

As shown in fig. 11, in the endoscopic imaging apparatus 20c, similarly to the endoscopic imaging apparatus 20b, a fixing member 36 is provided on the sheath 28d of the signal cable 28, and a protective tube 37 is covered therewith. Therefore, in the endoscope imaging apparatus 20c, as in the endoscope imaging apparatus 20b, the bonding strength of the signal cable 28 is high, and the bonding reliability of the signal cable 28 is high.

The endoscopic imaging device 20c further includes a cover 50 that covers the

electronic components

30 and 30a. The lid 50 is preferably made of metal, for example. By providing the metal cover 50, heat generated by the

electronic components

30 and 30a is conducted to the cover 50, and heat generated by the

electronic components

30 and 30a can be discharged to the outside of the endoscopic imaging device 20 c.

The cover 50 is made of, for example, stainless steel, copper alloy, graphite, or the like.

Further, the cover 50 is preferably joined to the connecting member 44, or the cover 50 and the connecting member 44 are preferably formed integrally. This increases the number of components that are thermally conductive by the

electronic components

30 and 30a, and thus, heat that may be transmitted to the imaging element 25 can be further reduced, and the heat can be efficiently discharged to the outside of the endoscopic imaging device 20 c.

When the cover 50 and the connecting member 44 are integrally formed, the cover 50 and the connecting member 44 are formed of the same metal.

The cover 50 and the coupling member 44 may be separate members. In this case, the cover 50 preferably holds the arm portions 44b so as to be closer to each other on the distal end 45b side than on the proximal end 45a side of the arm portions 44b of the coupling member 44. This makes it difficult for the opening 44c of the arm 44b and the projection 24c of the holding member 24 to fall off, and the holding member 24 and the coupling member 44 are more reliably fixed, resulting in an improvement in the rigidity of the endoscopic imaging device 20 c.

In the endoscopic imaging apparatus 20c, as in the endoscopic imaging apparatus 20 (see fig. 4), a gap 39 (see fig. 11) is preferably provided between an end portion 36b (see fig. 11) of the fixing member 36 on the rear end surface 44h side of the coupling member 44 and a front end surface 37a (see fig. 11) of the protective tube 37. As shown in fig. 8, a clearance 41 is preferably provided between the inner surface 37b of the protective tube 37 and the outer sheath 28d of the signal cable 28.

The present invention is basically constituted as described above. Although the endoscope imaging apparatus and the endoscope of the present invention have been described in detail above, the present invention is not limited to the above-described embodiments, and various improvements and modifications can be made without departing from the scope of the present invention.

Claims

1. An endoscopic imaging apparatus that acquires an image of an observation target, comprising:

a lens barrel having an imaging lens provided therein;

an imaging element that receives light having passed through the imaging lens and performs photoelectric conversion;

a circuit substrate electrically connected to the imaging element;

at least one optical component disposed between the lens barrel and the imaging element;

a holding member that connects the optical member and the lens barrel;

a signal cable electrically connected to the imaging element and having an outer sheath forming an outer periphery;

a fixing member provided on the sheath of the signal cable;

a protective tube covering the sheath of the signal cable; and

a coupling member that holds the signal cable provided with the fixing member with respect to the holding member,

the signal cable is fixed to the coupling member,

the protective tube is provided such that a front end surface thereof is positioned closer to the lens barrel side than a rear end surface of the connecting member on the opposite side of the lens barrel, and closer to the rear end surface side than the fixing member.

2. The endoscopic camera apparatus according to claim 1,

the signal cable is fixed to the connecting member by an adhesive.

3. The endoscopic camera apparatus according to claim 2,

the protective tube is softer than the adhesive in a cured state.

4. The endoscopic camera apparatus according to claim 1,

the connecting member covers the imaging element, the circuit board, and the optical member.

5. The endoscopic camera apparatus according to claim 2,

6. The endoscopic camera apparatus according to claim 3,

7. The endoscopic camera apparatus according to claim 4,

the connecting member is provided with a through hole.

8. The endoscopic camera apparatus according to claim 7,

the opening diameter of the through hole provided in the connecting member is 0.6mm or more.

9. The endoscopic camera apparatus according to claim 7,

the through hole provided in the coupling member is provided closer to the fixing member than the distal end surface of the protection pipe.

10. The endoscopic camera apparatus according to claim 8,

11. The endoscopic camera apparatus according to claim 1,

the endoscope image pickup apparatus includes:

a cover provided on the connecting member and covering the imaging element, the circuit board, and the optical member,

the cover is formed of metal.

12. The endoscopic imaging apparatus according to any one of claims 1 to 11,

there is a play between an inner face of the protective tube and the sheath of the signal cable.

13. The endoscopic imaging apparatus according to any one of claims 1 to 11,

the protective pipe is disposed with a gap provided between an end portion of the fixing member on the rear end surface side and the front end surface of the protective pipe.

14. An endoscope having the endoscopic imaging device according to any one of claims 1 to 13.